Is cursing one's father due to his separation from one's mother considered a departure from God's mercy, and what should one do about that?

If a father wrongs the mother by beating and assaulting her, his action is bad and forbidden, except within the bounds of Islamic law. Nevertheless, it is not permissible for children to curse their father, because honoring him and treating him kindly is obligatory, even if he mistreats them. If Allah has forbidden even saying "uff," then cursing is far more forbidden and a greater act of disobedience. The questioner must repent from this action, seek her father's forgiveness, and supplicate for him abundantly with good. Cursing a Muslim is serious, so what about a father? Sincere repentance may erase the sin of this curse.